Implementations of folding mechanisms for exterior rear-view mirrors in automotive vehicles are known which are provided with movement means for a mirror-carrying casing with respect to a support chassis fixed to the structure of a vehicle. Generally, such movement means are arranged in a detachable housing fixed to the mirror-carrying casing and essentially comprise an electric motor and one or more gears adapted for driving a rotating ring linked to the support chassis.
In Spanish patent ES 2158924, the mirror casing supporting the glass of the mirror can be folded by means of a motor secured in the support chassis by a hinge and which can fold under the effect of an impact from a use position. The hinge has a tubular piece fixed in the support chassis and a sleeve which is coaxially pressed by means of a spring against the tubular piece, as well as a limiting device for the rotating movement of the casing around the tubular piece.
This exterior mirror is extremely complex given that it requires two elements acting together by means of an swinging limiter, one of which is arranged on the casing and the other one is arranged coaxially with respect to the tubular piece in the hinge and where a socket disc is located operatively connected to the motor, provided with a rebated movement limiter with a projection and stop, one of both elements of which is configured at the foot of the mirror and the other one at the head of the mirror or in the socket disc.
Spanish patent ES-A-2166677 for an “Automatic Folding Mechanism for Exterior Rear-View Mirrors in Automotive Vehicles” describes a folding mechanism in which a rotating ring housed in a detachable housing fixed to a mirror-carrying casing is linked through positioning means to the support chassis, while at the same time it is linked to the housing through positional fixing means comprising a fixing rod and a compression spring arranged in a cavity of the detachable housing, the rod being adapted so that its projecting end is housed in grooves made on the rotating ring, all this for the purpose of limiting the rotation of the mentioned ring with respect to the housing in one of the rotating directions.
One of the ends of the grooves of the rotating ring must be configured in inclined planar shape so that when the fixing rod rotates with respect to the housing in the suitable direction, it causes the fixing rod to move due to the pressure of said inclined plane against the fixing rod, which leaves the groove sliding over its inclined plane and rests directly on the rotating ring. When the ring rotates in the reverse direction, the opposite end of the fixing groove, lacking an inclined plane, runs against the projecting end of the rod housed in the groove, therefore the rod is not moved, preventing the rotation of the ring with respect to the housing.
The positional fixing means formed by the fixing rod and the spring, as well as the cavity of the detachable housing intended to house them, increase manufacturing and assembly costs. Likewise, if the fixing rod is to prevent the rotation of the ring with respect to the housing in the opposite rotating direction, it is necessary to use different rotating rings to in turn change the end of the grooves provided with the inclined plane.